Wheeling register. [volume] (Wheeling, W. Va.) 1878-1935, 1887-03-17

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the puzzle of engineers and n~ayigators
f, since the settlement Of the country. As
I early ~ l126 the French aud spanish en-
ginecrS employed 81 peculiar device; Ina
msnse iron harruwS were dragged along
the bottom, being attached by stout cables
20 sailing vessels, and the mud thus stirred
up was swept away by the current and q
temporary channel secured. But in ne
I long time, So gentle was the current just
beyond the rivers mouth, the mud again
! ~hOaled up tIil the water OF the bar was
but I've OF six feet deep. The SptuiardS,
and after them the French again, tried
many devices, bat all IN vain. After the
American occupation thorough surveys
were made and the following facts eStab-
l'Shed:
|. The real mouth Of the Mississippi Is
al the last hlaii, near Baton Rouge. All
| ,he hayuu country, so called, below tins i
made land" Biologists estimate that
+.lOU years were required To make the
( region between Baton Rouge and the
mouth Of the river.
, At flood the river contains about ten
times aS much water Is 1t its lowest
/ some 5000, GOO gallons per secoiwi passing
| New Orleans, each gallon carrying a lew
| grains Ofsiit. The result l. that enough
silt i carried down the Mississippi each
year 10 ill one mile square 30 feet deep.
3 The conclusion from the foregoing
facts l. that f the volume OF the river
were uniform, or approximately 50. ITS
channel would be uniform, but with the
variations Of level the channel constantly
SniftS. plows out or shoals mp, and ~ soon
| IS the current Stacks. as il must Just be-
/ yOnd the mouth, the mud begins Ia drop
aud forms 4 har. The mouth OF the man
channel thus moves Onward into the gull
at an average rate OF loo feet = year, and
/ the crest OF the har mON CS on in advance OF
it-this crest being from a mile and 4 hal!
( tn a mile and th~ree-guIrterS ont into tn"
gulf beyond the real mouth of the river.
Ii was further shown that whenever one
| Of the mcUths called passes cloScdan-
/ other opened. Ii = Shcalat the Southwest
/ Pass closed it entirely. then there was 4
I barely paSSable channel ut South Pass, or
| PAS a D'Outre, and Nicr verse.
The hest known devices for getting of
| the har'' were well known a. "wHpiug'
rocking and dragging and when one
/ Large vessel had worked through the sub
marine bank Of tough mud, : the current
naturally followed her track, there was
/ always an easier passage for Others for 4
few DAYS after.
Many and novel were the devices sng,
prSted 10 overcome this difficulty, hut
/ popular favor finally settled on = canal via
| lake Pontchartrajn. The question became
$1,000 - ...Nl III 81 s.NAn- fNr mn
tccting the low lands, and for the latter
purpose outlets were proposed ut various
points 10 draw Of the surplus waters oi
I The Mississippi by side channels. so the
/ outlet system and the elual became
! associated in a general way in the popular
favor, and were approved by the govern
ment engineers. But when the subject
was submitted to Capt EIdS ne swept all
/ these plans aside, and submitted an en-
tirely new one, based upOA the following
laws rs to running water:
The caracity of a river current to carry
silt increases as the square or cube ct its
velocity, rs il may be a straight OF whirl-
/ ing current. a whirling wind takes IN
more dust than a straight wind, and Il
wind OF ten miles per hour more than
twice as much Is one of five miles per
hour" Thus, if We assume that current
I of one mile per hour will carry n grain OF
silt to the gallon OF water, q current of two
miles per hour will carry, not two grains,
but four or five. These figures are not
exact, they only illustrate the principle }
A deep channel, therefore, Is 10 be Sc
cured, not by dividing, but by concentrat'
ing the current. If you withdraw one-haii
the rivers volume, hat section below the
point OF withdrawal will slacken and
shoal up, the current dropping not one
halt, but three-fourths or more of its silt.
All great rivers flowing through alluvial
regions are making deltas; they drop silt
at their mouths, they maintain their chan
mel through the deposit because the mud
on each side drops to the bottom and SO
confines the channel. Thus they make
their " banks up to the level of the
highest floods. So the Mississippi has an
average depth Of over 100 feet below
Baton Rouge, till it reaches the gulr